Requirements for the
formwork board In any construction, monolithic reinforced concrete structures are always necessary, therefore it is impossible to do without formwork. For several centuries, wooden formwork has been used to construct such structures. It has proved itself quite well in the work, and the only drawback is the impossibility of using its elements in the future for other works.
The device of wooden formwork is not so high-tech, you just need to adhere to some rules in its manufacture:
- the thickness of the board for the formwork should be from twenty millimeters, and the width - up to two hundred millimeters;
- one side must be striated, namely the one that comes into contact with the solution;this condition is fulfilled without fail;
- moisture boards should be at least 25 percent, dry before use abundantly moistened with water.
What you need to remember when mounting the wooden formwork?
Of the prepared boards you need to put together the boards of the right size. For their connection, special wooden bars or cuttings from the same boards are used to create these shields. These bars are nailed at a distance of 0.5-1 m from each other, which depends on the expected load, that is, on the volume of the solution being poured.
Special attention should be paid to nails, their length is selected taking into account that they could be bent, and the length of the bend should be at least ten millimeters. The most optimal option is when the nail is clogged from inside the formwork to the outside.
When mounting a rectangular ribbon foundation, the boards for foundation formwork take a thickness of 40 to 50 centimeters. From the inside, the boards are fixed by spacers, outside - by stakes, which are clogged directly into the ground, very tightly to the boards taking a large pressure of the solution.
If there is a need for a higher foundation, more than twenty centimeters, then use special shields, the position of which is also fixed like boards.
A few more practical tips
If the decision on which board to make formwork is accepted, the production of shields should be paid special attention. They are knocked down so that the length of each of them is twenty-five millimeters larger than the side on which it will be installed, so that it becomes possible to fasten them in L-shaped fashion.
When assembling boards, it is necessary to use nails and not in any case self-tapping screws. The nail is bent, while the self-tapping screw can pop out under the pressure of a large mass of the solution. Eaves boards for formwork can later be used for any rough work, if you try and leave it clean.
Which board to make formwork depends on the technical conditions developed specifically for this or that configuration of the foundation. But doing this work, you should take into account a few more points:
- First, any formwork is mounted on the ground, after cleaning it from all sorts of debris.
- Secondly, this surface should be perfectly flat, without holes and bumps, without the possibility of its subsidence.
- Third, the formwork panels must be connected very tightly.
The wooden formwork will be of high quality if you carefully check the correct level and plumb line setting. After the foundation is ready, the dismantled boards must be cleaned of adherent concrete with scrapers and wire brushes.